Collapsible forming-tool.



1. H. HAMMANN.

- COLLAPslBLE FORNHNG TooL.

APPLICATION FILED AUG23| i915.

Patented May 16, 1916.

INVENTOR.

W vf/k/ A TTORNE YS.

WITNESS JOHN` H. HAMMANN, 0F' NORTHAIVIPTON, MASSACHUSETTS.

ooLLArsiBLE romaine-Toon T0 all whom 'it may concern Be it known that I, JOHN H. HAMMANN, a citizen of the United States of America, and residing in Northampton, in the county of Hampshire and State ofMassachusetts, have invented certain new and useful 1mprovements in Collapsible Forming-Tools, of which the followingl is a specification.

This invention relates toy collapsible forming tools and, while the invention is capable of general application, it is particularly adapted and designed for use in the manufacture of projectiles. The latter` are commonly made from hollow cylindrical blanks which are closed at one end. The open end of the blank is thereafter crimped inwardly or nosed down to form the point of the projectile andthis operation leaves an interior surface which converges axially near the open end from the full diameter of the tubular blank to an opening of less diameter, This converging surface is left rough by the nosing down operation and to conform to requirements must be finished smoothly and accurately to size.

The object of the invention is to provide an improved shaping tool to shape surfaces not readily accessible for ordinary tools and more particularly to provide a collapsible tool of this character which may be passed through narrow spaces to proper position and then conveniently expanded to an accurately adjusted position for the work to be done. U i A v The objects of the i vention will be clearly seen from the following description of' one preferred form of the improved tool, and the scope of the invention will be pointed out more particularly in the annexed claims.

Referring to the drawings-Figure 1 is a side elevational view of the forming tool; F ig. 2 is an end elevational view, partly in section, showing the cutters in expanded position to finish the converging interior surface of a shell; and Fig. 3 is a sectional plan view taken on the line3-3 of Fig. 2 and looking in the direction of the arrows.

Referring to these drawings in detail and particularly to Fig. 2, a represents a hollow shell to be finished, and b is the nosed down part thereof. Adjacent the part the interior surface of the shell converges from its full diameter, with an axially curved surface indicated by c, to an aperture d of reduced diameter. The latter affords the only means of access to the in- Speccation of Letters Patent.

Patented May 16, 1916.

Application filed August 23, 1915. Serial No. 46,973.

terior of the shell, and therefore the desirability of finishing or shaping the surface b conveniently, accurately, and quickly presents problems not solved by the use of ordinary tools.

v.In finishing a shell, there are several operations to be performed successively, and in practice these various steps are accomplished by a number of suitable tools mounted in a turret lathe. This `invention is, however, concerned primarily with only one operation, viz., the finishing of the curved interior surface c by suitable means which will now be describe i l represents a hollow spindle, formed at one end with an enlarged portion 2, which is arranged to be mounted in the turret of a turret lathe. Slidable within the spindle 1 is a rod 3 and fixed thereinl is a pin l which extends outwardly through a suitable slot 5 in the spindle into a cam slot 6: The latter 1s formed in a revoluble sleeve 7 mounted on the spindle 1 and held axially between a flange 8 and a collar 9 fixed to the spindle 1. A suitable operating handle 10 is secured to the sleeve 6 to permit convenient turning of the latter. i Y

The upper end of the rod 3 is forked as clearly shown in F ig. 3, and pivotally mounted in this forked end at 11 is a pair of cutter .blades l2. These cutters are mounted in overlapping relation and are movable through longitudinal slots in Jthe spindle l, as shown. The outer surfaces of the blades 12 are shaped to conform with the curved converging surface c of the projectile, and at their inner upper ends have slightly rounded surfaces 13. These surfaces are arranged, when the blades 12 are in their expanded positions, to abut the inclined surfaces 14 formed on the lower edge of a block 15. The latter is mounted in a slot in the upper end of spindle 1 and is movable by a screw 16 to adjust the blades 12 in an obvious manner. i

17 are suitable clamping screws which ex- .tend through slots in the block 15, whereby the latter may be held in various positions of adjustment.

In operation, when the sleeve 7 is rotated, the pin 4 and thus the rod 3 will be forced downwardly by the cam slot 6, whereby the cutters 12 will be drawn within the sleeve 3 in overlapping relation. When the cutters are so positioned, they pass freely through the small aperture Z into the interior of shell a. After the spindle has been inserted into the shell, the sleeve 7 is turned to force the pin 4 and rod 3 upwardly. The pin 4 xed to rod 3 rides into a horizontal part of the slot 6, and the rod 3 is then held rigidly in position during the cutting operation. As the cutters 12 are forced upwardly, the surfaces 13 of the cutters coact with the surfaces 14 of block 15 to force the cutters outwardly into a predetermined cutting position, whereby the converging surface c may be accurately finished. When necessary, as after the blades 12 have been sharpened, a compensatory adjustment of the cutters 12 may be made by turning the screw 16 after the clamping screws 17 have been loosened.

Thus, I have provided an improved form* ing tool which is collapsible to permit its entrance through a small aperture and which is subsequently expansible to finish surfaces diverging from said aperture.

It is recognized that various modifications may be made in the structure described without departing from the scope of my invention which is pointed out in the appended claims.

What I claim is:

l. A cutting tool, comprising, a sleeve adapted to be mounted in a lathe, a rod movable axially in said sleeve, axially arranged slots formed in the sleeve, cutters pivotally connected to said rod and movable in said slots, cam elements adjustably mounted in the sleeve and arranged to engage the cutters, and means'to move said rod arranged, when the rod is moved in one direction, to draw the cutters together within the sleeve and, when moved in the other direction, to force the cutters against said cam elements, whereby the cutters may be expanded into cutting position, all constructed and arranged so that interior surfaces may be iinished through an aperture of less diameter than that of the surfaces.

2. A forming tool for finishing interior surfaces through an opening of reduced diameter, comprising in combination, a hollow spindle, a rod Vmovable axially therein, longitudinally arranged slots formed in the spindle, cutters pivotally mounted on said rod and movable in said slots, camelements adjustably mounted in the spindle and arranged .:to engage the cutters, and means to move said rod operable to draw the cutters within the spindle or to move the cutters against said elements, whereby the cutters may be forced outwardly from .the spindle into a predetermined cutting position, said means comprising a sleeve rotatable on said spindle having a cam slot formed therein, and a pin on said rod extending through said spindle into said slot, whereby, when the sleeve is turned, the rod may be moved axially relative to the spindle.

3. A forming tool, comprising, a hollow spindle provided with longitudinal slots, a rod slidably mounted in the spindle, a pair of cutters pivoted in overlapping relation on the rod, means onl the spindle arranged to force the cutters in and out of said slots as the rod is moved longitudinally of the spindle and a cam sleeve rotatable on the spindle and operable to move the rod therein.

4. A forming tool, comprising, a hollow spindle provided with longitudinal slots, a rod slidably mounted n the spindle, a pair of cutters pivoted on the rod in overlapping relation and ground to out a inished surface on radial movement fromV the spindle, an adjustable cam surface on the spindle engageable by the critters to position the latter, a cam sleeve on the spindle operable to move the rod therein to and from engage ment with said adjustable cam whereby the cutters may be expanded to position for `their work or contracted to be taken from the work through narrow spaces.

JOHN H. HAMMANN.

copies of this patent may be obtained for ve cents each, byaddressing the "Commissioner of Patents, Washington, D. 0.. 

